Separator vessel having multiple parallel separator plates

ABSTRACT

This invention relates to a means for separating solids from fluid or gas, fluids from gas, and commingled immiscible fluids from each other when one portion of such fluids has a heavier specific gravity than the other. When used to separate commingled immiscible fluids the invention includes a vessel having a fluid inlet, a light fluid outlet and a heavy fluid outlet, the outlets being spaced from the inlet, and a plurality of spaced apart parallel separator screens positioned within the vessel between the inlet and the outlet arranged such that fluid flowing from the inlet to the outlet passes through the separator screens, each separator screen being a planar foraminous reticulum of integrally formed relatively small width and small thickness strands, all of which are longitudinally downwardly inclined providing a multiplicity of continuous uninterrupted downwardly inclined paths on which coalesced droplets of heavier fluid may travel towards the bottom of the vessel.

Unite States Patent urdock, Sr.

1 51 May 23, 1972 [72] Inventor: Forrest L. Murdock, Sr., 2420 East 24thSt., Tulsa, Okla. 74114 [22] Filed: Apr. 22, 1970 [21 Appl. No.: 30,843

Primary Examiner-Reuben Friedman Assistant ExaminerR. W. BurksAttorney-Head & Johnson ABSTRACT This invention relates to a means forseparating solids from fluid or gas, fluids from gas, and commingledimmiscible fluids from each other when one portion of such fluids has aheavier specific gravity than the other. When used to separatecommingled immiscible fluids the invention includes a vessel hav ing afluid inlet, a light fluid outlet and a heavy fluid outlet, the outletsbeing spaced from the inlet, and a plurality of spaced apart parallelseparator screens positioned within the vessel between the inlet and theoutlet arranged such that fluid flowing from the inlet to the outletpasses through the separator screens, each separator screen being aplanar foraminous reticulum of integrally formed relatively small widthand small thickness strands, all of which are longitudinally downwardlyinclined providing a multiplicity of continuous uninterrupted downwardlyinclined paths on which coalesced droplets of heavier fluid may traveltowards the bottom of the vessel.

6 Claims, 9 Drawing Figures Patented May 23, 1972 3,664,093

3 Sheets-Sheet I I/VVE/VTOR.

FORREST L- MURDOCK,SR

Patented ay 23, 1972 5 Sheets-Sheet 2 QQN I/VVENTOR' FORRESTL.MURDOCK,SR

If I I 7 ATTORNEYS SEPARATOR VESSEL HAVING MULTIPLE PARALLEL SEPARATORPLATES BACKGROUND, SUMMARY AND OBJECTS OF THE INVENTION The need for ameans for separating solids from fluid or gas and commingled immisciblefluids from each other is frequently encountered in the chemical andpetroleum industries. A typical example which will be utilized forpurposes of illustrating the invention, but which is by no means theonly application of the invention, is that of separating water entrainedin petroleum products, especially petroleum crude. Most crude oil hassome water entrained in it. In order for efficient and economicaltransportation and refining of crude oil it is important that as much aspossible of the water be removed and at the least expense.

The method of separating water from crude presently utilized in thepetroleum industry is to subject the crude to a sequence of steps. Onecommonly used step is that of subjecting the water bearing crude to aquiescent settling zone or tank wherein the water is given anopportunity to settle from the crude, the water being withdrawn from thebottom of the tank. Another step frequently used is to heat the waterbearing crude, thereby lowering the viscosity which permits the water tomore readily settle out. Another treatment includes subjecting the waterbearing crude to an electric field which, under proper conditions, tendsto cause small water droplets to coalesce into larger droplets whichmore easily settle out of the crude. An important means of treatmentincludes subjecting the water bearing crude to a filter material whichprovides a great surface area on which water may coalesce and form intolarge droplets which settle out of the crude. It is towards this lastmeans of separation, that is, positioning in an enclosed containerfacilitates explosing a large total surface area on which water dropletsmay coalesce for subsequent separation from the crude that thisinvention is primarily directed.

A common means of providing large surface areas for coalescing water incrude is the use of excelsior, and other similar products, both naturaland synthetic, normally used in an arrangement in which the fluid flowis vertically upward through the excelsior. While excelsior typeproducts are effective to a degree in achieving the desired results someproblems and limitations are encountered. Excelsior has a limited lifespan in that, being organic, it will decompose. Excelsior, or anyequivalent natural or synthetic fibrous type material, has a tendency toclog easily with dirt, debris, and other contamination so that, in manyinstances, frequent replacement is required. The results of clogging dueto collection of debris and contaminants tends to cause the fluid tochannel, that is, the fluid flows through the filter media in smallchannels so that only a relatively small percent of the filter medium isactually effectively utilized. Another difliculty with the use ofexcelsior and similar configured natural and synthetic materials is thatsuch materials are, by their nature, randomly oriented, having nopreferential direction of inclination of elongated components. For thisreason water droplets coalescing on such material are not preferentiallydownwardly oriented in their flow path, and therefore droplets easilydetach from horizontal portions of the filter medium and becomeresuspended in the fluid stream.

This invention provides a means for separating solids from fluid or gas,fluids from gas, and commingled immiscible fluids from each other whichovercome the disadvantages of known types of separators and whichparticularly overcome the disadvantages of known types of separators andwhich particularly overcome the disadvantages of excelsior typeseparator material.

It is therefore a general object of this invention to provide animproved means for separating commingled immiscible fluids.

Another object of this invention is to provide a means for separatingcommingled immiscible fluids of divergent specific gravities includingmeans of providing a large amount of surface area on which droplets ofheavier fluid may coalesce including means wherein all portions of suchsurface area are downwardly directed to provide uninterrupted downwardlyinclined paths on which coalesced droplets of heavier fluid may travel.

Another object of this invention is to present a separator forseparating solids from fluid or gas, fluids from gas, and immisciblefluids from each other in which the flow through the separator ishorizontal.

Another more particular object of this invention is to provide a vesselincorporating the improved separating means of this invention.

Another object of this invention is to provide an apparatus for mixingsolids and liquids with gas, solids with liquids, and for emulsifyingimmiscible fluids.

These as well as other objects of the invention will be understood inlight of the following description and claims, taken in conjunction withthe attached drawings.

DESCRIPTION OF THE VIEWS FIG. 1 is a cross-sectional view of a vesselincorporating the improved means for separating commingled immisciblefluids of this invention.

FIGS. 2 and 3 are cross-sectional views taken along the lines 2-2 and 33respectively of FIG. 1.

FIG. 4 is a side view, shown partially cut-away and in cross section, ofa heater-treater vessel incorporating the improved separating means ofthis invention FIGS. 5, 6, 7, 8 and 9 are fragmentary views of separatorscreens showing some of the various configurations which may beutilized.

DETAILED DESCRIPTION While the invention is equally as applicable to theseparation of solids and fluids from gas, solids from fluids, and oneimmiscible fluid from another, the invention will be described as itparticularly relates to the separation of one immiscible fluid fromanother.

Referring first to FIGS. 1, 2 and 3, an embodiment of the invention isillustrated. The separator includes a vessel generally indicated by thenumeral 10 having at the inlet end 11 a fluid inlet 12, and at outletend 13, a light fluid outlet 14 and a heavy fluid outlet 16, the lightfluid outlet 14 being above the heavy fluid outlet 16. The vessel mayalso include a gas outlet 18 in the upper portion 19 thereof, the vesselbottom being identified by numeral 21. While fluid outlet 16 is shown inoutlet end 13 it may be placed in bottom 21. In addition a fluid sumpmay be provided in bottom 21 for some applications.

Positioned within the vessel 10 are a plurality of spaced apart parallelseparator screens 20. The separator screens 20 are positioned betweenthe fluid inlet 12 and the outlets 14 and 16. In the illustratedarrangement each of the screens 20 extends from the top 19 to the bottom21 of vessel 10. Heavier fluid 22A collects in the bottom of the vesselwhile lighter fluid 22B collects in the upper portion. The interface 23between the lighter fluid 22B and the heavier fluid 23 is above thelower end of the filter screens 20. By means as shown in FIGS. 2 and 3the separator screens extend from the top 19 and are in contact with thesides of the vessel so that all fluid flow from the inlet 12 to thelight fluid outlet 14 must pass through the plurality of screens 20.

Screens 20 are arranged such that the angles of each (indicated by angleA) relative to the general direction of fluid flow, as indicated by thearrow 24in FIG. 1, is at least 15 and not more than Each of the filterscreens is a planar foraminous reticulum of integrally formed relativelysmall width and small thickness strands, all of which are longitudinallydownwardly inclined providing a multiplicity of continuous uninterrupteddownwardly inclined paths on which coalesced droplets of heavier fluidmay travel towards the bottom of vessel 10.

FIGS. 5-9 show enlarged portions of various configurations of filterscreens 20. While the separator screens may be formed of a variety ofmaterials, a preferred embodiment includes the use of expanded metal,that is, metal which has been manufactured by sequential spaced slittingfollowed by a stretching of the metal into diamond-shaped openings 25,such as shown in FIGS. 5 and 6. Each diamond-shaped opening issurrounded by strands 26 which interconnect into an integrally formedcomposite screen. Note that by reason of such arrangement droplets ofheavier fluid which coalesce as the commingled fluid passes through thefilter are provided with continuous uninterrupted downwardly inclinedpaths on which the droplets flow.

Separation of commingled fluids of divergent specific gravities isperformed essentially by providing an environment in which there is agreat amount of surface area on which droplets of the heavier liquid maycoalesce. The droplets grow in size until they are sufficiently large toovercome the surface tension of the commingled fluid and pass downwardlyin the fluid and collect in the heavier fluid stratum 22A in the bottomof the vessel. As previously stated, one of the most frequently utilizedmethods at the present time, and a method which has been utilized formany years, is subjecting commingled fluid to excelsior or some similarmaterial. The essence of this invention is the provision of latticeconfigured separator screens in which all portions of the latticeprovide an uninterrupted downward path on which coalesced droplets mayflow until they reach the bottom of the vessel. The separator screen ofthis invention does not provide any point or area at which droplets ofheavier fluid tend to leave the screen and fall into the flowing fluid.

It can be seen that coalesced droplets of heavier fluid which losecontact with a solid element and enter into the commingled fluid aresubject to being carried by the commingled fluid out of the vessel withthe lighter fluid stream. In addition, a droplet of heavier fluid whichbecomes detached from any physical support is subject to being dispersedinto the commingled fluid and broken into smaller droplets. By theprovision of this invention these possibilities are eliminated, or atleast substantially reduced. Physical support is provided on whichcoalesced droplets may travel by surface adhesion from the top to thebottom of the vessel without becoming detached from the path providedand therefore with reduced possibility of re-entering the commingledstream.

In the preferred embodiment, as shown in FIG. 1, the lower end 20A ofeach of the separator screens 20 is positioned downstream from the upperend 208. This means that each screen 20 tends to deflect fluid flowingtherethrough downwardly. The heavier fluid components, which tend tocoalesce onto the separator screens, are thereby urged downwardly towardthe bottom of the vessel by the effect of fluid flow. The lightercomponents of the commingled stream are forced to rise upwardly againstsuch downward deflection which further tends to separate the heaviercomponents.

The physical structure in which the separator means of this invention ishoused may vary considerably. FIG. 1 shows a very simple separatorvessel. FIG. 4 shows the incorporation of the means for separatingcommingled immiscible fluids of this invention as a part of an overallheater-treater. Heatertreater vessel 26 has an inlet end 26A and anoutlet end 268, the inlet end 26A has an inlet opening 28 therein bywhich commingled immiscible fluids enter the vessel. Outlet end 26Bincludes an upper lighter fluid outlet 30 and a lower heavier fluidoutlet 32. The vessel includes partitions 34 through 39, the partitionsbeing generally parallel to each other and spaced from each other.

Between partition 34 and inlet end 26A is formed a quiescent zone 40 inwhich the heavier components of the commingled fluid tend to settle tothe bottom. Fluid flows over the top of partition 34 and into a downwarddiverting chamber 42. The fluid flows underneath the partition 35 and upthrough a spreader 44, past heaters 46 wherein the temperature of thefluid is raised, and over the top of the partition 36.

The function of heaters 46 is to raise the temperatures of thecommingled fluid, reducing the viscosity, and thereby facilitating theseparation of the heavier fluid components.

Between partitions 36 and 37 is a second downwardly diverting chamber48. Fluid flows underneath partition 37 and upwardly through a separatorchamber 50. In chamber 50 are a plurality of spaced apart separatorscreens 20, the same as previously described in reference to FIG. 1.Separator screens 20 provide an exceedingly large total surface area onwhich coalesced drops of heavier fluid components may collect. Thecoalesced drops flow downwardly on uninterrupted paths to the lowerportion of the vessel as previously described. Fluid flows generallyhorizontally with slight upward inclination through the separatorchamber 50 and passes over the top of partition 38 into a third downwarddiverting chamber 52. Fluid flows from chamber 52 under partition 39 andupwardly within a final filter chamber 54. Within final filter chamber54 horizontal apertured plates 56 are provided having filter media 58,such as excelsior therebetween.

The function of filter media 58 is to collect physical contaminantcarried by the upwardly flowing stream and to afford the finalopportunity for coalesced heavier fluid droplets to fall out.

The down flow chambers 42, 48 and 50 are provided to obtain reversal offluid flow so that droplets of heavier fluid tend to be ejected from thefluid stream when the stream changes direction and moves upwardly in thesucceeding chambersv FIG. 4 is an example of the application of theseparating means of this invention to a heater-treater embodiment as maytypically by utilized in the petroleum industry for separating waterfrom crude petroleum.

It can be seen that the physical embodiment of the principles of thisinvention may vary considerably. The number of separator screensutilized will depend upon the environment in which separation is to beachieved. The divergents between the specific gravities of the heavierversus the lighter components of the commingled fluid is one of theparameters effecting the number of screens required. The thoroughness ofseparation desired is another factor, with more thorough separationrequiring a larger number of screens. The size of the openings throughthe screens varies according to the type of fluid being treated. Smalleropenings result in a greater number of strands per square foot of screenarea and therefore a greater total surface area on which heavier fluidcomponents may coalesce, however, smaller openings also are more easilyplugged by debris. Therefore the selection of the size of screenopenings is predicted primarily upon choosing a screen in which theopenings are just large enough to pass all expected contamination. Theangle declination A of the plane of the screens from the generaldirection of fluid flow depends also on a great variety of parameters,including the relative specific gravities of the fluid components, thefluid viscosity and the flow rate through the separator.

The invention provides a means of separating commingled immisciblefluids having many advantages over known arrangements. A separator isprovided having a very large total surface area on which droplets ofheavier fluid may coalesce while at the same time maintaining arelatively low impedance to fluid flow. The energy required to passfluid through the separator is small compared to other known separatingmeans. Another advantage is that servicing of the separator of thisinvention is minimized since the separation system does not depend uponforcing the commingled fluid through finely matted material. Theseparator plates 20 are arranged such that no clogging will occur if thescreens are selected having openings of a size sufficient to pass allexpected contamination. The life expectancy of the separator system ofthis invention, if proper materials are selected is practicallyunlimited.

The invention has been described as it relates to the specificapplication of separating one immiscible fluid from another. Ifprovision is made for more than one fluid interface within the vessel10, with an outlet 14 above each interface, it can be seen that theinvention may be used for separating three or more fluids, each having adifierent specific gravity, in the same way as two fluids are separatedin the above description.

When used to separate solids and fluids from gas, or solids from fluids,the invention functions is the same way as previously described. Theinclination of the separator screens 20 force the heavier componentsdownward towards the bottom of the vessel where they may be withdrawn,the lighter components passing against such downward deflection towardsthe top of the vessel. By this means solids from liquids, such as solidsfrom sewage effluent, dust from air or gas, cutting from drilling mud,and so forth, may be separated. This is not to imply that the inventionhas application to every separation problem and in many circumstancesother separation means or filter arrangements, may be more effective orless expensive.

By reversing the direction of flow through the vessel the effect of theinvention may be reversed. That is, opening 14 may be used for a heavyfluid inlet, opening 16 for a light fluid inlet, and opening 12 for anemulsion outlet. The same characteristics which cause separation in onedirection of fluid flow cause emulsification in the opposite fluid flowdirection. When the invention is used in an emulsifier, or mixer,usually higher flow rates may be employed compared to rates used forseparation. Fluid as used in the claims includes liquids, gases andvapors.

While the invention has been described with a certain degree ofparticularity it is manifest that many changes may be made in thedetails of construction and the arrangement of components withoutdeparting from the spirit and scope of this disclosure. The invention isnot limited to the embodiments disclosed but is limited only by thescope of the claim or claims, including the full rang of equivalency towhich each step thereof is entitled.

What is claimed:

1. A means for separating heavier from lighter components commingled influids, including commingled immiscible fluids, one having a heavierspecific gravity than the other, comprising:

a vessel having a fluid inlet, a light component outlet, and a heavycomponent outlet, the outlets being spaced from the inlet, the lightcomponent outlet being above the heavy component outlet; and

a plurality of spaced apart, paralleled separator screens positionedwithin said vessel between said inlet and said outlet openings arrangedsuch that fluid flowing from said fluid inlet to said light componentoutlet flows through said screens, each separator screen being a planarforaminous reticulum of integrally formed relatively small width andsmall thickness strands all of which are longitudinally downwardlyinclined providing a multiplicity of continuous uninterrupted downwardlyinclined paths on which heavier components may travel towards the bottomof said vessel for discharge outsaid heavy component outlet.

2. A means for separating heavier from lighter components commingled influids, including commingled immiscible fluids according to claim 1wherein said separator screens are formed of lattice configured expandedmetal.

3. A means for separating heavier from lighter components commingled influids, including commingled immiscible fluids according to claim 1 inwhich said vessel and said openings therein are arranged such that theflow of fluid therein from said inlet opening towards said outletopening is such that the direction of fluid flow is generally horizontaland wherein said separator screens are positioned at an angle of atleast 15 and not more than relative to the horizontal, the lowermostportion of each of said screens being displaced in the direction offluid flow relative to the uppermost portions.

4. A means for separating heavier from lighter components commingled influids, including commingled immiscible fluids according to claim 1wherein said separator screens are formed of slit and stretched expandedmetal, the apertures therein being of diamond sha e.

5. A means for separating eavrer from lighter components commingled influids, including commingled immiscible fluids according to claim 1wherein said vessel includes a heater compartment having a heater meanstherein, said heater compartment having communication with said inlet,and a second compartment having said separator screens therein, saidsecond compartment having communication with said outlets, and meanscommunicating fluid flow from out of said first compartment into saidsecond compartment.

6. A means for separating heavier from lighter components commingled influid, including commingled immiscible fluids according to claim 1 inwhich said vessel is in the form of a compartment within an elongatedseparator housing, the ends of said vessel being formed of partitions insaid housing spaced apart and parallel to each other, the first of saidpartitions terminating at the lower end above the bottom of saidseparator housing, the space between the bottom of said first partitionand the bottom of said separator housing providing said inlet, and saidsecond partition being a partial partition, the partition top edge beingbelow the top of said separator housing and the bottom edge being abovethe bottom of said separator housing, the spaces between the secondpartition and the top and bottom of said separator housing providingrespectively said light component outlet and said heavy componentoutlet.

1. A means for separating heavier from lighter components commingled influids, including commingleD immiscible fluids, one having a heavierspecific gravity than the other, comprising: a vessel having a fluidinlet, a light component outlet, and a heavy component outlet, theoutlets being spaced from the inlet, the light component outlet beingabove the heavy component outlet; and a plurality of spaced apart,paralleled separator screens positioned within said vessel between saidinlet and said outlet openings arranged such that fluid flowing fromsaid fluid inlet to said light component outlet flows through saidscreens, each separator screen being a planar foraminous reticulum ofintegrally formed relatively small width and small thickness strands allof which are longitudinally downwardly inclined providing a multiplicityof continuous uninterrupted downwardly inclined paths on which heaviercomponents may travel towards the bottom of said vessel for dischargeoutsaid heavy component outlet.
 2. A means for separating heavier fromlighter components commingled in fluids, including commingled immisciblefluids according to claim 1 wherein said separator screens are formed oflattice configured expanded metal.
 3. A means for separating heavierfrom lighter components commingled in fluids, including commingledimmiscible fluids according to claim 1 in which said vessel and saidopenings therein are arranged such that the flow of fluid therein fromsaid inlet opening towards said outlet opening is such that thedirection of fluid flow is generally horizontal and wherein saidseparator screens are positioned at an angle of at least 15* and notmore than 90* relative to the horizontal, the lowermost portion of eachof said screens being displaced in the direction of fluid flow relativeto the uppermost portions.
 4. A means for separating heavier fromlighter components commingled in fluids, including commingled immisciblefluids according to claim 1 wherein said separator screens are formed ofslit and stretched expanded metal, the apertures therein being ofdiamond shape.
 5. A means for separating heavier from lighter componentscommingled in fluids, including commingled immiscible fluids accordingto claim 1 wherein said vessel includes a heater compartment having aheater means therein, said heater compartment having communication withsaid inlet, and a second compartment having said separator screenstherein, said second compartment having communication with said outlets,and means communicating fluid flow from out of said first compartmentinto said second compartment.
 6. A means for separating heavier fromlighter components commingled in fluid, including commingled immisciblefluids according to claim 1 in which said vessel is in the form of acompartment within an elongated separator housing, the ends of saidvessel being formed of partitions in said housing spaced apart andparallel to each other, the first of said partitions terminating at thelower end above the bottom of said separator housing, the space betweenthe bottom of said first partition and the bottom of said separatorhousing providing said inlet, and said second partition being a partialpartition, the partition top edge being below the top of said separatorhousing and the bottom edge being above the bottom of said separatorhousing, the spaces between the second partition and the top and bottomof said separator housing providing respectively said light componentoutlet and said heavy component outlet.